Abstract:
:Serum levels of prolactin were determined in nonbreeding male and female canvasbacks (Aythya valisineria) from mid-April to late June to evaluate the temporal changes occurring during spring. During this time interval, serum prolactin levels increased 1.5- to 2-fold in both males and nonlaying females (P less than 0.01). Serum prolactin levels of males and females exposed to natural lighting and temperature at Delta, Manitoba (50 degrees 11'N, 98 degrees 19'W), steadily increased from mid-April when the daylength was 14 hr light and peaked in mid-June when daylength was 16.25 hr light. Administration of exogenous estradiol via slow-release subdermally implanted capsules in females with intact reproductive systems had a marginal effect on reducing the seasonal increase in prolactin. Exogenous testosterone in similar slow-release capsules implanted subdermally in males had no influence on circulating prolactin levels.
journal_name
Gen Comp Endocrinoljournal_title
General and comparative endocrinologyauthors
Bluhm CK,Phillips RE,Burke WHdoi
10.1016/0016-6480(89)90160-3subject
Has Abstractpub_date
1989-11-01 00:00:00pages
286-91issue
2eissn
0016-6480issn
1095-6840pii
0016-6480(89)90160-3journal_volume
76pub_type
杂志文章abstract::Although present at relatively low number in the testis, spermatogonial stem cells (SSCs) are crucial for the establishment and maintenance of spermatogenesis in eukaryotes and, until recently, those cells were investigated in fish using morphological criteria. The isolation and characterization of these cells in fish...
journal_title:General and comparative endocrinology
pub_type: 杂志文章,评审
doi:10.1016/j.ygcen.2014.06.018
更新日期:2014-10-01 00:00:00
abstract::Understanding reproductive profiles and timing of reproductive events is essential in the management and conservation of humpback whales (Megaptera novaeangliae). Yet compared to other parameters and life history traits, such as abundance, migratory trends, reproductive rates, behavior and communication, relatively li...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2019.03.013
更新日期:2019-08-01 00:00:00
abstract::The growth hormone (GH) gene has been characterized for a number of fishes and used to establish phylogenetic relationships and as a candidate gene for studies of genetic variation in connection with growth traits. In this study, we report the genomic structure of Nibea coibor GH (designated as ncGH) including its 5'-...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2009.03.030
更新日期:2009-09-15 00:00:00
abstract::High levels of the amino acid neurotransmitter glutamate were found in the goldfish hypothalamus and pituitary using high performance liquid chromatography with fluorometric detection. A specific polyclonal antibody to glutamate was generated in the rabbit for immunocytochemistry. Localization studies demonstrated tha...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.0103
更新日期:1996-08-01 00:00:00
abstract::Sublethal doses of potassium thiocyanate (KSCN), an iodide competitor, depressed thyroidal radioiodide uptake of fed laboratory rainbow trout at 11 degrees, but did not depress either plasma levels of T4 (L-thyroxine) and T3 (triiodo-L-thyronine) or radioiodide incorporation into plasma iodothyronines. Furthermore, pl...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(83)90094-1
更新日期:1983-07-01 00:00:00
abstract::Pinealectomized and intact chicks raised under cyclic (14L:10D) and noncyclic (OL;24L) conditions of environmental lighting were sampled 60 hr and 6 weeks after pinealectomy to evaluate the effects of pineal ablation on plasma and ocular melatonin concentrations. Little or no immunoreactive melatonin was present in pl...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(85)90114-5
更新日期:1985-06-01 00:00:00
abstract::The presence of cholecystokinin (CCK), originally isolated from porcine small intestine, has been reported in a diversity of invertebrates ranging, from cnidarians to protochordates, but so far, not in echinoderms. We have used immunohistochemical techniques to demonstrate the presence of cells expressing CCK-like imm...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(91)90026-3
更新日期:1991-08-01 00:00:00
abstract::In altricial songbirds, food restriction in early development has adverse effects on various physiological systems. When conditions improve birds can accelerate growth, but this compensatory strategy is associated with long-term adverse consequences. One system affected by altered growth rates is the hypothalamic-pitu...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2015.08.001
更新日期:2015-10-01 00:00:00
abstract::Gonadotropin-releasing hormone (GnRH) of vertebrates is now believed to have multiple functions in addition to its role as a hypophysiotropic hormone, as originally defined. Recently, it has been shown that GnRH occurs also in the ascidians, which are considered ancestral chordates. Here the author shows that GnRH ind...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.2001.7728
更新日期:2001-12-01 00:00:00
abstract::The effects of calcium on steroidogenesis and cyclic AMP production in chicken granulosa cells were examined. For the expression of full steroidogenic effects by LH, forskolin, and 8-bromo cyclic AMP the presence of calcium in the incubation medium was essential, the optimal concentration being 1 mM. Moreover, calcium...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(86)90100-0
更新日期:1986-04-01 00:00:00
abstract::Stress-induced inhibition of innate immune activity has been observed in a variety of wild birds and may increase chances of infection because this activity constitutes the first line of defense against pathogens. We previously reported that the transient elevation of plasma corticosterone (CORT; the primary avian glu...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2019.02.002
更新日期:2019-05-01 00:00:00
abstract::Neonatal handling of captive vertebrates can shape the development of their hypothalamo-pituitary-adrenal (HPA) axis and alter their ability to respond to stressful stimuli later in life. However, the long-term effects of such handling on this endocrine axis in free-living species are not well understood. We investiga...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2013.03.004
更新日期:2013-06-01 00:00:00
abstract::Vertebrate eggs are surrounded by an extracellular glycoprotein coat termed zona pellucida (ZP). Integrity of ZP is critical for a correct embryo development. Two zona pellucida protein genes (zpb and zpc) from European eel were characterized, specific qPCR assays developed and their expression in immature males and f...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2012.06.003
更新日期:2012-09-01 00:00:00
abstract::We studied the in vitro effects of JH III and ecdysterone on RNA synthesis and secretory activities of the left colleterial gland (LCG) in mature females of Periplaneta americana during the reproductive cycle. We found that RNA synthesis is a cyclic and highly dynamic process. The major increases in poly(A)- RNA synth...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90301-2
更新日期:1988-07-01 00:00:00
abstract::During metamorphosis, the tadpole neuroendocrine brain is a major target for the organisational effects of hormones acting via both endocrine feedback mechanisms and local hormone production. While the receptor-mediated actions of thyroid hormones in brain development have been well described, there is evidence that t...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2007.02.011
更新日期:2007-10-01 00:00:00
abstract::Current views on Agnathan phylogeny favor the hypothesis that the genera of holarctic lampreys belong to a single family (Petromyzontidae) and form an interrelated progression in which Petromyzon is near to Ichthomyzon at the base of the phylogenetic tree and Lampetra is the most derived. A stock similar to that of co...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1998.7203
更新日期:1999-02-01 00:00:00
abstract::Receptors for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) in turkey cerebral cortex were characterized using two approaches: (1) in vitro radioreceptor binding of [125I]-VIP, and (2) effects of peptides from the PACAP/VIP/secretin family on cyclic AMP formation. T...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2004.03.007
更新日期:2004-06-01 00:00:00
abstract::Abnormalities in calcium (Ca(2+)) homeostasis are reported in horses with several pathological conditions; however, there is little information on Ca(2+) regulation in horses. The objectives of the present study were to determine the Ca(2+) set-point in healthy horses, to determine whether the Ca(2+)/parathyroid hormo...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/s0016-6480(02)00621-4
更新日期:2003-02-15 00:00:00
abstract::While there is considerable structural evidence that insulin-like growth factors (IGFs) share a long evolutionary history, little is known about the conservation of IGF function. In order to address this, we have made recombinant hagfish IGF, hence allowing characterization of an IGF from a representative of the primi...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1996.6802
更新日期:1997-01-01 00:00:00
abstract::We demonstrated the presence of specific binding sites for bullfrog luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in a testicular crude plasma membrane fraction of the bullfrog, Rana catesbeiana. The equilibrium analysis of the binding showed that a straight line was fitted to the Scatchard plot of L...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(86)90207-8
更新日期:1986-02-01 00:00:00
abstract::GPR-30, now named as GPER (G protein-coupled estrogen receptor) was first identified as an orphan receptor and subsequently shown to be required for estrogen-mediated signaling in certain cancer cells. Later studies demonstrated that GPER has the characteristics of a high affinity estrogen membrane receptor on Atlanti...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2014.11.011
更新日期:2015-01-15 00:00:00
abstract::Previous studies have provided evidence that D-Asp plays a role in steroid-mediated reproductive biology in amphibians, reptiles, birds and mammals. To examine the molecular involvement of D-Asp on steroidogenic pathway regulation, we analysed the expression of StAR, P450 aromatase and 5αRed2 mRNAs in Pelophylax escul...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2011.10.006
更新日期:2012-01-01 00:00:00
abstract::Several antisera specific to neuropeptides of vertebrates were applied to sections of the earthworm Eisenia fetida Sav. Some of them were able to reveal specific neurones of the supraoesophageal ganglion: h-GHRF, CRF, Leu- and Met-enkephalin, dynorphin, substance P, CCK-8, and CCK-8S. A map of different areas or nucle...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(87)90132-8
更新日期:1987-03-01 00:00:00
abstract::The vertebrate oxytocin and vasopressin receptors form a family of G-protein-coupled receptors (GPCRs) that mediate a large variety of functions, including social behavior and the regulation of blood pressure, water balance and reproduction. In mammals four family members have been identified, three of which respond t...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2011.10.011
更新日期:2012-01-01 00:00:00
abstract::Interrenal tissue from embryonic and larval rainbow trout (Oncorhynchus mykiss) was cultured in vitro and exposed to various doses of adrenocorticotropin (ACTH) to document the ontogeny of interrenal responsiveness to tropic stimulation. Resting and acute stress-induced changes in whole-body cortisol levels in vivo we...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1995.1122
更新日期:1995-09-01 00:00:00
abstract::The present study in seasonally breeding spotted snakehead Channa punctatus, for the first time in nonmammalian vertebrates, demonstrated correlation between reproductive phase-dependent testicular expression of ligand Jag1/receptor Notch1 and spermatogenic events. Testicular transcriptome sequencing data from our ear...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2018.05.014
更新日期:2018-09-15 00:00:00
abstract::Cholecystokinin (CCK) radioimmunoassay and immunocytochemistry were used to localize the expression of CCK-like peptides in the gut, brain, and skin of Xenopus laevis during development from fertilization through metamorphosis to the adult form. CCK-like peptides were first detected in the gut shortly before food was ...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/0016-6480(88)90213-4
更新日期:1988-11-01 00:00:00
abstract::Ghrelin (GRLN), cocaine and amphetamine regulated transcript (CART), neuropeptide Y (NPY), and cholecystokinin (CCK) are neuropeptides involved in the regulation of appetite and feeding in vertebrates. We examined pre- and postprandial changes in the expression of plasma GHRL and mRNAs encoding GRLN, CART, NPY, and CC...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2012.01.022
更新日期:2012-04-01 00:00:00
abstract::In dairy cows, heat stress depresses appetite, leading to decreased food intake, a negative energy balance, and modifies ghrelin levels. Ghrelin is a gut-brain peptide with two major forms: acylated, with an O-n-octanoylated serine in position 3, and nonacylated. To date, the effect of heat stress and estrous cycle on...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1016/j.ygcen.2016.06.006
更新日期:2016-09-01 00:00:00
abstract::We studied effects of in vitro conditions on the steady-state distribution and exchange of thyroid hormones (TH) between red blood cells (RBC) and plasma of rainbow trout. At steady state at 12 degrees C the RBC contained 5-11% of L-thyroxine (T4), 14-23% of 3,5,3'-triiodo-L-thyronine (T3), and 23-24% of 3,3',5'-triio...
journal_title:General and comparative endocrinology
pub_type: 杂志文章
doi:10.1006/gcen.1997.7028
更新日期:1998-02-01 00:00:00